Chapter 015. Headache (Part 6) doc

Headache Part 6 Positron emission tomography PET activation in migraine.. Moreover, lateralization of changes in this region of the brainstem correlates with lateralization of the head

Chapter 015 Headache

(Part 6)

Positron emission tomography (PET) activation in migraine

In spontaneous attacks of episodic migraine (A) there is activation of the

region of the dorsolateral pons (intersection of dark blue lines); an identical pattern

is found in chronic migraine (not shown) This area, which includes the noradrenergic locus coeruleus, is fundamental to the expression of migraine Moreover, lateralization of changes in this region of the brainstem correlates with lateralization of the head pain in hemicranial migraine; the scans shown in panels

B and C are of patients with acute migraine headache on the right and left side,

respectively (From S Afridi et al: Arch Neurol 62:1270, 2005; Brain 128:932, 2005.)

Figure 15-3

Posterior hypothalamic gray matter activationon positron emission tomography (PET) in a patient with acute cluster headache Posterior

hypothalamic gray matter activation on positron emission tomography (PET) in a

patient with acute cluster headache (A) (From A May et al: Lancet 352:275,

1998.) High-resolution T1 weighted MRI obtained using voxel-based

morphometry demonstrates increased gray matter activity, lateralized to the side of

pain in a patient with cluster headache (B) (From A May et al: Nat Med 5:836,

1999.)

Diagnosis and Clinical Features

Diagnostic criteria for migraine headache are listed in Table 15-4 A high index of suspicion is required to diagnose migraine: the migraine aura, consisting

of visual disturbances with flashing lights or zigzag lines moving across the visual field or of other neurologic symptoms, is reported in only 20–25% of patients A headache diary can often be helpful in making the diagnosis; this is also helpful in assessing disability and the frequency of treatment for acute attacks Patients with episodes of migraine that occur daily or near-daily are considered to have chronic migraine (see "Chronic Daily Headache," below) Migraine must be differentiated from tension-type headache (discussed below), the most common primary

headache syndrome seen in clinical practice Migraine at its most basic level is

headache with associated features, and tension-type headache is headache that is featureless Most patients with disabling headache probably have migraine

Table 15-4 Simplified Diagnostic Criteria for Migraine

Repeated attacks of headache lasting 4–72 h in patients with a normal physical examination, no other reasonable cause for the headache, and:

At least 2 of the following

features:

Plus at least 1 of the following features:

Throbbing pain Photophobia and phonophobia

Aggravation by movement

Moderate or severe intensity

Source: Adapted from the International Headache Society Classification

(Headache Classification Committee of the International Headache Society, 2004)

Patients with acephalgic migraine experience recurrent neurologic symptoms, often with nausea or vomiting, but with little or no headache Vertigo

can be prominent; it has been estimated that one-third of patients referred for vertigo or dizziness have a primary diagnosis of migraine